"The challenges are many, but most revolve around the variability of Wi-Fi due to environmental considerations," Stanger says. "For instance, most Wi-Fi broadcasts at around 2.4GHz. Unfortunately the resonating frequency of water is also 2.4GHz, and people are comprised of mostly water. So, the more that people congregate, the more the Wi-Fi radio patterns vary. So the question becomes, how can we normalize patterns when the very usage we envisage generates disruptions to those patterns?"

Stanger isn't saying how his company has done it, only that it involves proprietary coding.

Phone maker Nokia is also working on an interesting way to determine location in an indoor environment.

As part of a , Nokia recently participated in a demo showing how unused portions of the TV spectrum can deliver information to people according to their location.